Study of spatio-temporal variability of the maximum daily rainfall

Tunisia presents a large spatio-temporal variability of rainfall which was largely observed in the last years. This variability is influenced by several local and regional factors. The objective of this paper is to study the characteristics of the space and temporal variability of maximum daily rainfall in the state of Bizerte, located in the low valley of the medjerda basin and to seek the factors (topography, latitude, longitude, proximity of the sea, the speed direction of the wind …) who influence this variability to introduce them in the rainfall cartography. In order to study the space-time variability of the maximum daily rainfall, we used the frequential analyses, the principal component analysis (PCA) and the variography. Results show an important spatio-temporal variability caused by the effect of the several factors such as the topography, the depressions and the effect of the sea whose behavior of the rains differs from the South to the North of the state. These Observations are introduced into the cartography which is carried out by various methods of interpolation, the deterministic methods and geostatistics in aim to establish the maps of isohyets.